Предмет: Алгебра, автор: Георгий008

{3x+5y= -9 {2х-у= 7
Решить систему уравнений

Ответы

Автор ответа: prettypushkova
1

{3х + 5у = -9

{2х - у = 7

- - - - - - - - - -

{у = 2х - 7

{3х + 5 · (2х - 7) = -9

3х + 10х - 35 = -9

13х = 35 - 9

13х = 26

х = 26 : 13

х = 2

у = 2х - 7 = 2 · 2 - 7 = 4 - 7 = -3

Ответ: (2; -3).

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